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            <div><h3 class="title">
                <a name="asio.reference.execution__execute"></a><a class="link" href="execution__execute.html"
                                                                   title="execution::execute">execution::execute</a>
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    <p>
        <a class="indexterm" name="asio.indexterm.execution__execute"></a>
    </p>
    <p>
        A customisation point that executes a function on an executor.
    </p>
    <pre class="programlisting"><span class="keyword">constexpr</span> <span class="identifier">unspecified</span> <span
            class="identifier">execute</span> <span class="special">=</span> <span class="identifier">unspecified</span><span
            class="special">;</span>
</pre>
    <p>
        The name <code class="computeroutput"><span class="identifier">execution</span><span
            class="special">::</span><span class="identifier">execute</span></code> denotes a customisation point
        object.
    </p>
    <p>
        For some subexpressions <code class="computeroutput"><span class="identifier">e</span></code>
        and <code class="computeroutput"><span class="identifier">f</span></code>, let <code
            class="computeroutput"><span class="identifier">E</span></code> be a type such that <code
            class="computeroutput"><span class="keyword">decltype</span><span class="special">((</span><span
            class="identifier">e</span><span class="special">))</span></code>
        is <code class="computeroutput"><span class="identifier">E</span></code> and let <code
            class="computeroutput"><span class="identifier">F</span></code> be a type such that <code
            class="computeroutput"><span class="keyword">decltype</span><span class="special">((</span><span
            class="identifier">f</span><span class="special">))</span></code>
        is <code class="computeroutput"><span class="identifier">F</span></code>. The expression <code
            class="computeroutput"><span class="identifier">execution</span><span class="special">::</span><span
            class="identifier">execute</span><span class="special">(</span><span class="identifier">e</span><span
            class="special">,</span> <span class="identifier">f</span><span class="special">)</span></code> is
        ill-formed if <code class="computeroutput"><span class="identifier">F</span></code>
        does not model <code class="computeroutput"><span class="identifier">invocable</span></code>,
        or if <code class="computeroutput"><span class="identifier">E</span></code> does not model either
        <code class="computeroutput"><span class="identifier">executor</span></code> or <code
            class="computeroutput"><span class="identifier">sender</span></code>. Otherwise, it is expression-equivalent
        to:
    </p>
    <div class="itemizedlist">
        <ul class="itemizedlist" type="disc">
            <li class="listitem">
                <code class="computeroutput"><span class="identifier">e</span><span class="special">.</span><span
                        class="identifier">execute</span><span class="special">(</span><span class="identifier">f</span><span
                        class="special">)</span></code>,
                if that expression is valid. If the function selected does not execute
                the function object <code class="computeroutput"><span class="identifier">f</span></code>
                on the executor <code class="computeroutput"><span class="identifier">e</span></code>, the
                program is ill-formed with no diagnostic required.
            </li>
            <li class="listitem">
                Otherwise, <code class="computeroutput"><span class="identifier">execute</span><span
                    class="special">(</span><span class="identifier">e</span><span class="special">,</span> <span
                    class="identifier">f</span><span class="special">)</span></code>,
                if that expression is valid, with overload resolution performed in a
                context that includes the declaration <code class="computeroutput"><span class="keyword">void</span>
                <span class="identifier">execute</span><span class="special">();</span></code>
                and that does not include a declaration of <code class="computeroutput"><span class="identifier">execution</span><span
                    class="special">::</span><span class="identifier">execute</span></code>.
                If the function selected by overload resolution does not execute the
                function object <code class="computeroutput"><span class="identifier">f</span></code> on
                the executor <code class="computeroutput"><span class="identifier">e</span></code>, the program
                is ill-formed with no diagnostic required.
            </li>
        </ul>
    </div>
    <h5>
        <a name="asio.reference.execution__execute.h0"></a>
        <span><a name="asio.reference.execution__execute.requirements"></a></span><a class="link"
                                                                                     href="execution__execute.html#asio.reference.execution__execute.requirements">Requirements</a>
    </h5>
    <p>
        <span class="emphasis"><em>Header: </em></span><code class="literal">asio/execution/execute.hpp</code>
    </p>
    <p>
        <span class="emphasis"><em>Convenience header: </em></span><code class="literal">asio/execution.hpp</code>
    </p>
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                Distributed under the Boost Software License, Version 1.0. (See accompanying
                file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
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